The ultimate value of diagnostic technology is its capacity to improve patient outcomes by leading to improved management decisions and care. Thus, assessment of diagnostic tests requires evaluation not only of diagnostic performance, but also determination of the incremental diagnostic information provided and the impact of this information on resulting interventions and relevant patient outcomes. The primary objective of this project is to estimate the lifetime incremental clinical and cost-effectiveness (assessed using discounted direct medical expenditures) and cost-utility (incremental cost per additional quality- adjusted life years [QALYs]) associated with the selected use of new breast imaging modalities in screening women at high breast cancer risk (strong family history, BRCA1/2 mutation, contralateral breast cancer), with evaluation of suspicious but non-diagnostic findings on standard screening mammogram and classification/staging of newly diagnosed breast cancer. Two separate but closely linked sets of analyses will be conducted: (1) a set of clinical decision analyses will guide individual patient-level decision making; and (2) a set of cost-effectiveness analyses will guide policy decision making. Model results also will guide the selection of test interpretation operating points for the new modalities evaluated in Projects 1-3. As more expensive new technologies that may improve diagnosis, management and health outcomes of women with breast cancer, breast imaging modalities are ideal candidates for such analysis. The clinical and cost-effectiveness analyses will provide timely assessment of the incremental clinical value and cost-effectiveness of new breast imaging modalities in improving health outcomes, survival and quality adjusted survival, using the estimates of diagnostic performance assessed in Projects 1-3. The results of the proposed clinical and cost-effectiveness analyses will help inform clinicians, patients, insurers and policy makers. Model results will provide the information necessary to help guide use of these and other new breast imaging modalities to maximize the health of individuals and populations, given budget constraints and demands for and opportunities of competing health care interventions.